A population study on irritable bowel syndrome and mental health

Background: Irritable bowel syndrome (IBS) is commonly thought to he associated with psychologic distress. However. in some studies only persons who had sought medical cart: for IBS (IBS patients) showed an increased frequency of psychiatric symptoms, and nonpatients did not differ significantly from normal subjects. Our aims were 1) to estimate the prevalence of IBS in the population aged 18-45 years, 2) to find the proportion seeking medical care for IBS, and 3) to compare IBS subjects with normals, and IBS patients with IBS nonpatients with regard to mental health. Methods: Questionnaires on IBS symptoms and the General Health Questionnaire (GHQ) were mailed to 5000 randomly sampled persons aged 18-45 years. The response rate was 58%. Results: IBS was found in 7.4% of the men and 13.3% of the women. Those who had sought medical attention had more severe symptoms. The Likert mean score on the GHQ was 4.7 (95% confidence interval, 4.4-5.0) points higher for the IBS group than for normals (P < 0.001). There was no difference in GHQ scores between IBS patients and nonpatients. Conclusions: The results indicate that IBS per se is associated with more psychiatric distress, regardless of medical care-seeking. Seeking medical care is associated with more severe IBS symptoms.